Haemorrhagic Pituitary Adenoma

39 year old female under medical treatment for a prolactin-secreting pituitary adenoma. 1st follow up MRI shows enlarged pituitary gland with subacute hemorrhage e.g. high signal on T1 and T2 WIs with methemoglobin-fluid level on Axial T2 {arrow}. At that time; patient was clinically stable without any acute manifestations. Patient continued bromocriptine therapy. 2nd MRI 1 year later and clinical follow up revealed marked improvement. Serum prolactin returned to normal as well.
Pituitary apoplexy is an acute clinical syndrome caused by either hemorrhage or infarction of the pituitary gland. An existing pituitary adenoma is usually present but it can occur with healthy glands in few isolated cases. The gland suddenly enlarges and may cause compression of structures adjacent to the sella. This can lead to a number of signs and symptoms, including sudden loss of visual acuity with a chiasmal field defect, oculomotor palsies, and severe headache. In addition, the patient may experience decreased sensorium, hypopituitanism, and subarachnoid irritation, the latter being secondary to hemorrhage
The message: hemorrhage within pituitary adenomas may be seen without clinical evidence of pituitary apoplexy which is an acute clinical syndrome (as in present case).
References:
1. Osborn et al 2004: Diagnostic Imaging: Brain. II-2-28:31. Amirsys.
2. Ostrov et al 1989: Hemorrhage Within Pituitary Adenomas: How Often Associated with Pituitary Apoplexy Syndrome?. AJR 153:153-160.
Credit: Dr Ahmed Haroun
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